Why Study Continental Aquatic Systems? - Freshwater Ecology: Concepts and Environmental Applications - page 11

approach grounded with sound scientific information (Vogt et al., 1997).
Productive application of science requires explicit recognition of the role of
temporal and spatial scale in the problems being considered and the role
of the human observer (Allen and Hoekstra, 1992). Thus, I attempt to con-
sider scale throughout the topic. As discussed later, understanding of the
mechanisms of problems such as nutrient pollution, flow alteration in
rivers, sewage disposal, and trophic interactions has led to successful mit-
igation strategies. Many of our rivers are cleaner than they were several
decades ago. Future efforts at protection are more likely to be successful if
guided by informed aquatic ecologists interested in protection of our wa-
ter resources.
SUMMARY
1. Clean water is essential to human survival, and we rely most heavily
on continental water, including streams, lakes, wetlands, and
groundwater.
2. The global renewable supply of water is about 39,000 km 3 per year,
and humans use about 54% of the runoff that is reasonably
accessible. Thus, clean water is one resource that will be limited
severely with future growth of the human population and increases in
the standard of living. Local problems with water quality and supply
may lead to political instability.
3. Economic analysis of the value of clean water is difficult, but factors
to consider include the value of clean water for human use, the value
of fisheries, and recreational use of aquatic habitats. The global
benefits of these uses translate into hundreds of billions of dollars
worth of benefit each year. Intangible benefits include preservation of
nongame species and native ecosystems.
4. The study of the ecology of inland waters will lead to more sound
decisions regarding aquatic habitats as well as provide a solid basis
for future research.
QUESTIONS FOR THOUGHT
1. Why are you interested in studying aquatic ecology, and is such study
important?
2. What is the difference between fluxes and compartments in water
cycles, and what types of units are typically used to describe them?
3. What are some potential economic benefits to maintaining water
quality?
4. What are the potential dangers in approaching conservation of
aquatic resources from a purely economic viewpoint?
5. List three “trade-offs” that are potentially involved in protecting
native species in regulated rivers by attempting to mimic natural water
discharge patterns.